Pipe tong



Aug, Q, 1942.

H. E. GRAU PIPE TONG Filed May 1, 1939 Herberf '15 Gram,

INVENTOR.

' ATTORNEYS Patented Aug. 4, 1942 PIPE TONG Herbert E. Grau, Vernon, Calif, assignor to Byron Jackson 00., Huntington Park, 'Calif., a corporation of Delaware Application May 1, 1939, Serial No. 270,986

3 Claims.

This invention relates generally to wrenches or tongs, and is directed particularly to improving the gripping means with which well pipe tongs are usuall equipped.

Pipe tongs of the type employed in making up and breaking out joints between sections of well pipe, such as drill pipe and well casing, are usually equipped with one or more toothed dies designed to grip the pipe or joint. Experience has proven that a die having only two teeth in engagement with the object to be gripped provides the most effective gripping action, more than two teeth preventing sufficient penetration of the teeth to avoid slipping of the die and tong circumferentially of the object.

A principal object of this invention is to provide a tong having gripping means which will positively grip the pipe and prevent slipping of the tong on the pipe.

A further object is to provide a novel and improved die having a plurality of sets of teeth, and to' provide a tong having a cooperating socket in which the die may be mounted in any one of a plurality of oriented positions to dispose a selected set of teeth in gripping position.

A still further object is to provide a pipe tong having a novel and particularly effective die which is mounted therein in a manner to adequately support the die against the thrusts imposed thereon.

Yet a further object is to provide a pipe tong having novel and improved retaining means for releasably holding the die in its socket.

The various objects and advantages of my invention will be fully understood from the following description of a preferred form of the invention, reference being had to the accompanying drawing, in which:

Figure 1 is a plan view of a tong head embodying the invention;

Figure 2 is a vertical sectional view taken on line 22 of Figure 1;

Figure 3 is a horizontal sectional view taken on line 3-3 of Figure 2; and

Figure 4 is a perspective view of the novel die.

The tong illustrated in Figure 1 is of the type generally employed for handling drill pipe or well casing, and includes a handle or lever H, and a plurality of jaws l2, l3, I4 and [5 adapted to be latched about a pipe l6. Mounted in one of the jaws, preferably the heel jaw I2, is a die I! of novel construction which will be described in detail hereinafter. The die is so disposed in the jaw as to have a pair of teeth projecting radially inwardly of the bore of the jaw into gripping engagement with the pipe. As an initial pull in a clockwise direction is exerted on the extended outer end of the lever II, the teeth of the die grip the pipe and prevent the tong from moving bodily about the pipe. The subsequent application of increased force to the lever then causes the jaws to be tightly clamped about the pipe, the teeth of the die being simultaneously pressed into the pipe and thus insurin against relative rotation between the pipe and the tong head.

In accordance with the present invention the die I! consists of an elongated body having a plurality of pairs of teeth uniformly spaced about the periphery thereof. In the illustrated embodiment the die is generally cruciform in transverse section, and has four pairs of gripping teeth 2|, 22, 23, and 24. As most clearly illustrated in Figures 3 and 4., the pairs of teeth are formed by shaping arcuate grooves or flutes 25, 26, 21, and 28 at the corners of the square formed by the four rectangularly related flat surfaces 29, 30, 3|, and 32. I prefer to bevel off the outer portions of the arcuate grooves, as indicated at 33 in Fig. 3, to form fiat faces at right angles to the outer flat surfaces 29, 30, 31, and 32. In this manner the teeth of each pair are parallel to each other and are symmetrically disposed with respect to a plane extending through the center of the die and the mid-point of the arcuate groove between the teeth.

The die is mounted in the jaw I2 in a slot 35 conforming in contour to the shape of the die. As shown in Figure 3, the slot opens into the inner bore of the jaw, and is symmetrical with respect to a radial plane through the axis of the pipe opening in the jaws, whereby a pair of teeth 2 l, 2| project equidistantly into the pipe opening into gripping engagement with the pipe. By conforming the die slot to the external contour of the die, the die is rigidly supported over its entire area with the exception of the protruding portions of the two active teeth.

Inasmuch as the die is formed of four identical quadrants, it ma be inserted in the slot in any one of four different oriented positions to dispose any one of the four pairs of teeth in active position. The effective life of the die is thus four times that of a die having only one set of teeth.

It will be observed from Figure 3 that the corners of the die slot 35 are relieved at 31 to avoid any possibility of injury to the edges of the inactive teeth when in use.

The particular shape of die illustrated affords an exceptionally strong and rigid mounting capable of withstanding the large shearing and compressive forces set up during operation of the tong. The convex portions of the socket cooperate with the concave flutes in the die to distribute the turning moment over a large area, and also assume their proportionate share of the radially outwardly directed pressure. When a rotative force is applied to the tong in the direction indicated by the arrow in Fig. 3, the trailing tooth 2| is adequately supported against shearing stress by the flat surface 35' in the slot.

The die and its slot are of a shape which lends itself readily to economical manufacture. The die may be rolled or forged from square or octagonal bar stock, and the die slot may be machined by a broaching operation.

Referring now to the novel retaining means, it will be observed from Fig. 2: that the die is retained in the slot by means engaging both ends of the die, so that in the event the die should become broken, no part of it can drop out of the slot. In the illustrative embodiment a permanent obstructionis formed in one end of the slot, as by a plate 4| welded in the slot. A retractible plunger 42 overlies the opposite end of the die, and is yieldingly retained in operative position by a compression spring 43 engaging an enlarged head 44 on the plunger. The bore 45 housing the compression spring is closed by a plug 46.

It will be apparent that this form of retainer is exceedingly simple and easily manipulated to permit removal of the die, and yet it effectively retains the die against accidental removal.

While I have shown a die having four pairs of gripping teeth, it will be understood that this is for illustrative purposes only, and that a die having a greater or lesser number of pairs of teeth may be provided if desired. Other variations or modifications will be apparent to those skilled in the art, and hence I do not wish to be limited to the specific details herein set forth.

I claim:

1. In combination, a tong die comprising an elongated body having a plurality of identical groups of gripping teeth disposed in equally spaced relation about the periphery thereof, and a pipe tong jaw having a die socket therein opening laterally into the pipe bore of said jaw for mounting said die with a selected group of gripping teeth projecting laterally inwardly beyond said pipe bore, said socket comprising symmetrically disposed groups of walls defining identical angular recesses adapted to receive the inactive teeth of said die, and the walls of said socket being constructed and arranged to engage the respective surfaces of said die when the latter is oriented to any one of a plurality of positions wherein a group of teeth project through the lateral opening in said socket.

2. In combination in a pipe tong, a jaw member and means for tensioning it about a pipe, said jaw having a face adapted to closely approach said pipe and having a die socket adapted to contain a die, a die for positioning in said socket, said die being prismatic in form, with a plurality of pipe-penetrating edges arranged in pairs, the two edges of each pair being adjacent each other and the die surface therebetween being re-entrant, all said pairs of edges being symmetrically disposed about a central axis of the die; said socket extending parallel to and opening into the pipe-approaching face of said jaw and being shaped to contact and support said die over substantially all its peripheral surface except one of said pair of edges, and the surface between those edges, said edges projecting through said opening into pipecontacting position.

3. In combination, a pipe tong jaw in part defining a bore for receiving a pipe and having a die socket therein extending parallel to the pipe bore and opening'laterally into said bore, and a tong die in said socket, said die comprising an elongated body having a plurality of identical groups of longitudinally extending grippingteeth, the groups being disposed in equally spaced relation about the periphery of the die, and said socket having walls defining a plurality of longitudinally extending recesses disposed in equally spaced relation about the periphery of said socket, said recesses being adapted to receive said groups of teeth on said die, said socket being so positioned and oriented in said jaw that one of the groups of teeth on 1 the die project through said lateral opening into pipe-engaging position in the pipe bore, said recesses and-said opening being symmetrically disposed about the axis of said socket, whereby said die in insertable in said socket in any one of a plurality of differentl oriented positions to project different groups of said teeth through said lateral opening.

HERBERT E. GRAU. 

